The invention generally relates to an optical sensor for detecting objects within an area to be monitored.
Optical sensors of this type can be embodied as light scanners, light barriers, reflective light barriers, distance measuring sensors and the like. To detect objects in an area to be monitored, the optical sensors comprise optical and electronic components, in particular, a transmitter for emitting light rays and a receiver for receiving light rays. Additional electronic components are provided which are mounted on circuit boards. The components include, in particular, an evaluation unit in the form of a microcontroller or the like in which an object-detection signal is generated at the receiver output. Cables or connectors are typically provided as electrical connecting means which are positioned inside at least one casing with therein-disposed integrated optical and electronic components for the optical sensor.
The casing, or each casing, used for an optical sensor typically comprises a casing body for accommodating the components, wherein this casing body can be closed off with a lid. In addition, exit windows that allow the transmitting light rays and the receiving light rays to pass through are provided in the walls of the optical sensor casing.
The connecting means are integrated into the casing by means of separate joining processes and pressing-in operations, such that they are secured in position. In addition, separate seals must be provided for tightly sealing the joining locations between the casing and the connecting means.
The lid and the exit window or windows must furthermore be secured in casing openings and sealed in, preferably by means of ultrasound welding or gluing. These additional production processes considerably increase the time required for producing the optical sensor and thus lead to an undesirable increase in the production costs. Apart from that, problems occur with sealing means of this type, especially if relatively large areas must be sealed, because irregularities during the application of the sealing means result in leaks which allow humidity or dirt to enter the sensor inside space.